Dehydration Condensation Research Articles

Recent advances in pyrolysis of cellulose to value-added chemicals

Lignocellulosic biomass has gained growing interest as a promising substitute for the production of renewable and sustainable chemicals and fuels as the dwindling fossil-fuel reserves. Pyrolysis without using any chemical reagent is an effective method to depolymerize cellulose into kinds of value-added chemicals. Herein, we summarized recent progress about non-catalytic and catalytic pyrolysis of cellulose into specific chemicals, including levoglucosan, 1-hydroxy-3,6-dioxabicyclo[3.2.1]octan-2-one, levoglucosenone, furans, aromatics, and olefins via dehydration, aromatization, and aldol condensation, etc. An analysis and summary of the optimal conditions of these value-added chemicals by catalytic pyrolysis of cellulose are benefit to develop better production methods. In addition, the potential challenges and future perspectives for the pyrolysis of cellulose to chemicals are also discussed to provide a feasible direction for relevant researchers to advance industrialization.

High-efficient double-cross-linked biohybrid aerogel biosorbent prepared from waste bamboo paper and chitosan for wastewater purification

This work prepared a double-cross-linked biohybrid aerogel (DCBA) bead biosorbent from waste bamboo paper and chitosan by sequential physical (hydrogen bonding and electrostatic interaction between -COO- and -NH3+ groups) and chemical (polymerization reaction between -COOH and -NH2, dehydration condensation between Si-OH and -OH) cross-linkings. The resulting DCBA bead was applied to remove cationic (Methylene blue, MB) and anionic (Congo red, CR) dyes in both single and binary systems. The MB and CR adsorption capacities of DCBA bead increased with increasing adsorbent dosage, contact time, temperature and initial dye concentration. With increasing solution pH, the MB adsorption capacity increased, while that for CR increased first and then decreased. The maximal adsorption capacities for MB and CR were 653.3 and 559.6 mg/g, respectively, in the single system. The thermodynamic analysis results showed a spontaneous and endothermic adsorption process. DCBA bead had a good stability and reusability with the removal efficiencies of 49.4% and 60.6% for MB and CR, respectively, after five cycles of adsorption-desorption. In the binary system, the adsorption of MB was inhibited by CR, while the removal of CR was enhanced by MB.

Catalytic Amination of Phenols with Amines.

Given the wide prevalence and ready availability of both phenols and amines, aniline synthesis through direct coupling between these starting materials would be extremely attractive. Herein, we describe a rhodium-catalyzed amination of phenols, which provides concise access to diverse anilines, with water as the sole byproduct. The arenophilic rhodium catalyst facilitates the inherently difficult keto-enol tautomerization of phenols by means of π-coordination, allowing for the subsequent dehydrative condensation with amines. We demonstrate the generality of this redox-neutral catalysis by carrying out reactions of a large array of phenols with various electronic properties and a wide variety of primary and secondary amines. Several examples of late-stage functionalization of structurally complex bioactive molecules, including pharmaceuticals, further illustrate the potential broad utility of the method.

Transformation of sulfamethoxazole by sulfidated nanoscale zerovalent iron activated persulfate: Mechanism and risk assessment using environmental metabolomics

The threat caused by the misuse of antibiotics to ecology and human health has been aroused an extensive attention. Developing cost-effective techniques for removing antibiotics needs to put on the agenda. In current research, the degradation mechanism of sulfamethoxazole (SMX) by sulfidated nanoscale zerovalent iron (S-nZVI) driven persulfate, together with the potential risk of intermediates were studied. The degradation of SMX followed a pseudo-first order kinetics reaction with kobs at 0.1176 min-1. Both SO4•− and •OH were responsible for the degradation of SMX, and SO4•− was the predominant free radical. XPS analysis demonstrated that reduced sulfide species promoted the conversion of Fe (III) to Fe (II), resulting in the higher transformation rate of SMX. Six intermediates products were generated through hydroxylation, dehydration condensation, nucleophilic reaction, and hydrolysis. The risk of intermediates products is subsequently assessed using E. coli as a model microorganism. After E.coli exposure to intermediates for 24 h, the upmetabolism of carbohydrate, nucleotide, citrate acid cycle and downmetabolism of glutathione, sphingolipid, galactose by metabolomics analysis identified that SMX was effectively detoxified by oxidation treatment. These findings not only clarified the superiority of S-nZVI/persulfate, but also generated a novel insight into the security of advanced oxidation processes.

Chain-ring covalently interconnected cellulose nanofiber/MWCNT aerogel for supercapacitors and sensors.

Bending multi-walled carbon nanotubes (MWCNTs) into rings and structuring them into aerogels is difficult. In this study, cellulose nanofiber (CNF)-MWCNT composite fibers with chain-ring structures were prepared by covalently interconnecting carboxylated CNF and aminated MWCNT by dehydration condensation, solving the problems of the formation of MWCNT aerogels and their phase separation during the compounding process and providing CNF-based aerogels with electrical conductivity. The covalently interconnected aerogels (CAs) had hierarchical porous structures with mechanical resilience and chain-ring fibers, which drove the CNF and MWCNT to form a continuous homogeneous network resulting in a high compression resistance of 269.02 kPa. The CA-based flexible all-solid-state supercapacitor had a quality specific capacitance of 114.8 F g-1, a capacitance retention rate of 94.78% and a Coulomb efficiency of 100%. The CA-based flexible sensor can sense different pressures with a stable response for 1000 cycles. This first study of pulling and bending MWCNT through CNF is expected to inspire more applications of MWCNTs in the fields of flexible supercapacitors and sensors.

HOAc catalyzed three-component reaction for the synthesis of 3,3'-(arylmethylene)bis(1H-indoles).

An efficient HOAc catalyzed three-component reaction of 2-(arylethynyl)anilines with arylaldehydes has been achieved, which leads to the generation of 3,3'-(arylmethylene)bis(1H-indoles) with good to excellent yields and high regioselectivity under transition-metal-free conditions. Four new C-C and C-N bonds were effectively formed in a one-pot procedure. Subsequent research on the reaction mechanism indicated that the reaction likely involved the processes of intramolecular cyclization and cascade intermolecular dehydration condensation.

The largest Se-4f cluster incorporated polyoxometalate with high Lewis acid-base catalytic activity.

A 4p-4f cluster incorporated polyoxometalate (POM), namely, H18{[(H4pic)4Eu10Se13O28(H2O)12](α-GeW9O34)4·40H2O (1-Eu, H4pic = isonicotinic acid), has been first synthesized and characterized. 1-Eu features an interesting four-shell structure, representing the largest Se-4f cluster incorporated POM known to date. Besides, 1-Eu exhibits excellent Lewis acid-base catalytic activity and reusablity in catalyzing the gram-scale dehydration condensation reaction of hydrazines and 1,3-diketones to synthesize polysubstituted pyrazoles.

Sonication - and γ-ray-mediated biomolecule-liquid metal nanoparticlization in cancer optotheranostics

Due to their unique characteristics, gallium-based liquid metal (LM) nanoparticles have been applied in various research fields. LM nanoparticle surface-modification design is essential for enhancing the original LM properties and physicochemical multifunctionalization. This study developed core-shell type nanoparticles based on eutectic gallium-indium and various biomolecules such as gelatin, deoxyribonucleic acid, lecithin, and bovine serum albumin using a sonicator and γ-ray radiator. In particular, the synthesized gelatin-functionalized LM nanoparticles exhibited excellent water dispersibility, unique morphology, uniform particle size, low toxicity, characteristic optical absorbance, potent photothermal conversion, high intracellular penetration, powerful photothermal anticancer efficacy, and functionalization with a fluorescent probe via dehydration condensation. The synthesized functional LM nanoparticles displayed in vivo fluorescent diagnosis of the targeted tumor location due to the enhanced permeability and retention effect. Moreover, the photothermal function of the LM nanoparticles was spatiotemporally activated by a biologically penetrable near-infrared laser to trigger targeted tumor ablation in mice. Thus, this study has provided an LM platform to design an effective, authentic nanoparticularization method and advance optotheranostics in cancer treatment.

High-efficiency electrochemical decomposition of artificial sweetener aspartame using a Ti3+ self-doped TiO2 nanotube arrays anode

Artificial sweeteners have attracted growing concern considering their large usage, wide detection and ecological toxicity in the last decade. In this work, high-efficiency decomposition of artificial sweetener aspartame was investigated by using a Ti3+ self-doped TiO2 nanotube arrays electrode. Effects of current density, initial concentration and inorganic anions on the degradation kinetics were studied. Results showed that the electrochemical degradation of aspartame followed pseudo-first-order kinetics, and the rate constant was 0.039 min−1 at a current density of 2 mA cm−2. The electrochemical degradation was not susceptible to nitrate, and the degradation was significantly enhanced by chloridion. Twenty-four transformation products were identified by UPLC-Orbitrap-MS/MS, and possible electrochemical degradation pathway was proposed. The degradation process of aspartame mainly included hydroxylated, demethylation, dehydrogenation, dehydration condensation and side-chain cleavage. Quantitative structure-activity relationship model revealed that the potential risks in electrolysis process should not be ignored before complete mineralization of aspartame. Energy consumption was greatly reduced in the presence of Cl-, and the lowest value for 90% aspartame degradation was 0.07 Wh L−1. The findings presented here demonstrate that electrocatalysis exhibits high efficiency in degrading aspartame and is potentially suitable for eliminating artificial sweeteners from wastewaters.

In-depth study on the extraction and mechanism of high-purity chitin based on NADESs method

Deep eutectic solvents (DESs) have been widely applied in biomass extraction due to their low toxicity, low cost, easy degradability, and other excellent characteristics. However, there are few reports on extraction of chitin, an important part of biomass, via DESs method, let alone the study of its related mechanism. Therefore, a novel natural deep eutectic solvents (NADESs) system consisting of lactic acid and choline chloride was proposed for the extraction of chitin. After optimizing the reaction process conditions, the obtained chitin with high purity up to 99.33% was prepared, which was comparable to the results obtained by the conventional method. And analysis results of the aforementioned products showed that the prepared chitin was acylated with a degree of 0.43. Moreover, the potential mechanism in the preparation process was explored. Free H+ in NADESs was confirmed to be the main reason for decalcification. Meanwhile, by constructing covalent bond, the hydrogen bond in NADESs was able to dissolve the protein bound to chitin, and then forming a new NADESs system, which further verified the essence of the acylation phenomenon was dehydration condensation between acid and -OH of chitin. Most importantly, the experiments as well as in-deep theoretical studies provide a directional reference that preparation of chitin from marine sources can be realized by utilizing natural resources.

A novel multiemissive Ln/covalent-organic frameworks for ratiometric detection of 2,6-dipicolinic acid

As one of the specific biomarkers of anthrax, timely, sensitive and accurate detection of 2,6-dipicolinic acid (DPA) plays an important role in preventing biological weapons attacks and disease outbreaks. Here, multiemission Eu3+/covalent- organic framework (COFDTA-TFP) and Tb3+/COFDTA-TFP were constructed by the coordination between Eu3+ or Tb3+ with fluorescent COFDTA-TFP which was prepared by amine-aldehyde dehydration condensation between 2,5-diaminoterephthalic acid and 2,4,6-triformylphloroglucinol for the first time. The Eu3+/COFDTA-TFP and Tb3+/COFDTA-TFP can emit non-overlapping fluorescence of COFDTA-TFP and Eu3+ or Tb3+, which was used to ratiometric detection of DPA. Due to the strong coordination between the nitrogen atoms in the pyridine ring and the oxygen atoms in the carboxyl group of DPA with Eu3+ or Tb3+, DPA replaced coordinated H2O to sensitize fluorescence of Eu3+ or Tb3+ by “antenna” effect but fluorescence of COFDTA-TFP with two-dimensional lamellar structure was kept constant as a reference. The linear range and detection limit of ratiometric fluorescence sensor based on Eu3+/COFDTA-TFP for detection of DPA are 0.01–12 µM and 4.2 nM, respectively. The linear range and detection limit of ratiometric fluorescence sensor based on Tb3+/COFDTA-TFP for detection of DPA are 0.01–9.0 µM and 2.9 nM, respectively.

Dual-functional intelligent gelatin based packaging film for maintaining and monitoring the shrimp freshness

Dual-functional intelligent food packaging film for maintaining and monitoring food freshness has gained a growing number of attentions in food field. Herein, we introduced a smart gelatin-based packaging film integrating real-time monitoring and maintaining food freshness. In detail, through a two-step de-solvation method, gelatin particles were fabricated and further used for preparing oil-in-water (O/W) lavender essential oil Pickering emulsions (LEOPs). LEOPs and Alizarin (ALI) were integrated into the gelatin matrix of the three-dimensional (3D) network via intermolecular hydrogen bonding and dehydration condensation, respectively, to develop intelligent active packaging films (GL-ALI-LEOPs). GL-ALI-LEOPs exhibited excellent antibacterial and antioxidant properties and a sensitive, reversible, and rapid response to pH/NH3. Benefiting from good mechanical properties, light barrier properties and hydrophobicity of modified gelatin-based films, GL-ALI-LEOPs are readily processed into food packaging bags and smart tags. GL-ALI-LEOPs were successfully employed as an eco-friendly, low-cost, bacteriostatic and pH/NH3 quick-responsive smart trademark for real-timely monitoring and maintaining the freshness of shrimp.

Inhibition of organosilane/ATP@HQ self-healing passivator for pyrite oxidation

Organosilane, with functional organic groups attached to inorganic silicon atoms, exhibits excellent passivation performance for pyrite. However, a considerable number of micro-cracks will gradually appear on the surface of passivation film under long-term corrosion of oxidizing medium, resulting in a significant decrease of passivation effect. To improve the stability and long-term performance of organosilane coating, a novel passivator (PT-ATP@HQ) with self-healing function was prepared to inhibit the oxidation of pyrite. We chose 3-mercaptopropyltrimethoxysilane (Prop-SH) and tetraethoxysilane (TEOS) as the host coating (PT), and attapulgite clay (ATP) loaded with 8-hydroxyquinoline (8-HQ) was used to endow the coating with better passivation and self-healing performance. The electrochemical and chemical leaching results showed that the addition of ATP@HQ greatly improved the passivation performance of PT coating. The passivation efficiencies of total Fe and SO42− reached to 88.1% and 79.2%, respectively. We also found that the protective capability of the scratched PT-ATP@HQ coating can be recovered automatically through 8-HQ release from ATP. The passivation and self-healing mechanisms were investigated by FT-IR, XPS, 29Si NMR, and other characterization methods, which were as follows: firstly, the organosilanes hydrolyzed to form highly active silanol groups, then dehydration condensation reaction occurred between silanol molecules and ATP@HQ to obtain cross-linked network structure connected by Si–O–Si bonds. After that, Si–OH groups reacted with the hydroxyl groups of pyrite to form Fe–O–Si bonds, thereby an inert and dense passivation film attached to the surface of pyrite. Once the passivation film is locally damaged, 8-HQ will automatically release to repair the cracks.

Green Copolymers Based on Poly(Lactic Acid)—Short Review

Polylactic acid (PLA) is a biodegradable and biocompatible polymer that can be applied in the field of packaging and medicine. Its starting substrate is lactic acid and, on this account, PLA can also be considered an ecological material produced from renewable resources. Apart from several advantages, polylactic acid has drawbacks such as brittleness and relatively high glass transition and melting temperatures. However, copolymerization of PLA with other polymers improves PLA features, and a desirable material marked by preferable physical properties can be obtained. Presenting a detailed overview of the accounts on the PLA copolymerization accomplishments is the innovation of this paper. Scientific findings, examples of copolymers (including branched, star, grafted or block macromolecules), and its applications are discussed. As PLA copolymers can be potentially used in pharmaceutical and biomedical areas, the attention of this article is also placed on the advances present in this field of study. Moreover, the subject of PLA synthesis is described. Three methods are given: azeotropic dehydrative condensation, direct poly-condensation, and ring-opening polymerization (ROP), along with its mechanisms. The applied catalyst also has an impact on the end product and should be adequately selected depending on the intended use of the synthesized PLA. Different ways of using stannous octoate (Sn(Oct)2) and examples of the other inorganic and organic catalysts used in PLA synthesis are presented.

Thermodynamics for complex formation of boric acid and borate with hydroxy acids and diols

The complex formation of boric acid (B(OH)3) and borate (BOH4-) with glycolic acid, lactic acid, 2-hydroxybutyric acid, 3-hydroxybutyric acid, malic acid, and (s)-1,2-propanediol in aqueous solutions has been investigated using 11B NMR and mass spectroscopy. The formation constants and the thermodynamic parameters, ΔH° and ΔS°, of the 1:1 and 1:2 complexes of boric acid for the hydroxy acid (B-HA) systems were compared with those for the polyol (B-OL) systems previously reported, together with those for a polyol of (s)-1,2-propanediol presently examined. The 1:1 complex formation was enthalpically driven in both B-HA and B-OL systems. In the former, the enthalpic gain is caused by the structural change of boric acid, accompanied by the dehydration condensation of boric acid with hydroxy acid. In the latter, the enthalpic gain only arises from the dehydration condensation of borate with polyol. The ΔH° values for the B-HA and B-OL systems are comparable with each other, despite the different numbers of dehydration of water molecules, i.e., one and two water molecules, respectively. The formation of 1:2 complex was entropically driven in the B-HA systems, while that in the B-OL systems was enthalpically progressed. This difference between the two systems is attributed to the flexibility of isolated ligand molecules. Since the isolated hydroxy acids form the intramolecular hydrogen bond, the entropic gain of the hydroxy acids is generated as the hydroxy acid is bound to 1:1 complex due to the breaking of the intramolecular hydrogen bond. Thus, the stabilities of the complexes in the B-HA systems mainly depend on the gain for the freedom of ligand.

Synthesis of hydrophilic copper(II) complexes of 5,10,15,20-tetraaryl-5,15-diazaporphyrins substituted with carboxy or (2,3-dihydroxypropyl)carbamoyl groups

Porphyrins containing hydrophilic auxiliaries have received considerable attention. Herein we report the first examples of strongly hydrophilic copper(II) complexes of 5,10,15,20-tetraaryl-5,15-diazaporphyrins (TADAPs) substituted with carboxy or (2,3-dihydroxypropyl)carbamoyl groups. Metal-templated cyclization reactions of a common dipyrrin precursor with nickel(II) or copper(II) acetate afforded the corresponding metal(II) complexes of 5,10,15,20-tetrakis(4-alkoxycarbonylphenyl)-5,15-diazaporphyrin (M-TADAP-COOR; M = Ni, Cu) as air-stable 19[Formula: see text] radical cations, which were reversibly interconvertible with 20[Formula: see text]- and 18[Formula: see text]-electron states by redox reactions. NMR spectroscopy of 20[Formula: see text] and 18[Formula: see text] Ni-TADAP-COORs revealed antiaromatic and aromatic characteristics, respectively. Alkaline hydrolysis of the 19[Formula: see text] Cu-TADAP-COOR afforded a carboxylic acid, Cu-TADAP-COOH, which was freely soluble in water under basic conditions, but poorly soluble under neutral or acidic conditions. Dehydrative condensation of Cu-TADAP-COOH with 2,3-bis((tert-butyldimethylsilyl)oxy)propan-1-amine followed by deprotection of the silyl groups afforded an amide, Cu-TADAP-CONHR, with four (2,3-dihydroxypropyl)carbamoyl groups. Although the 20[Formula: see text] Cu-TADAP-CONHR was poorly soluble in water, oxidation of its DAP ring notably changed the solubility, and the resulting 18[Formula: see text] dication was homogeneously dispersed in neutral water. Cyclic voltammetry of the present TADAP derivatives showed the 21[Formula: see text]/20[Formula: see text], 20[Formula: see text]/19[Formula: see text] and 19[Formula: see text]/18[Formula: see text] redox couples in the range of −1.8 to +0.2 V vs. Fc/Fc[Formula: see text]. Furthermore, Cu-TADAP-CONHR exhibited reversible redox processes in neutral water. This study shows that TADAP could be a potential platform for the development of hydrophilic DAP-based materials.

Regulating interlayer spacing with pillar and strain structures in Ti3C2 MXene layers by molecular welding for superior alkali metal ion storage

An ion insertion type in two-dimensional (2D) materials has attracted extensive attention making 2D materials as promising energy storage materials. However, the interlayer spacing plays a key role in the design of 2D materials with fast ions de-intercalation dynamics and high-rate capability. Here, an unprecedented and convenient organic molecular welding approach was proposed to controllably tune different interlayer spacings in Ti3C2 MXene layers, resulting in pillar and strain-xDA-Ti3C2 structures by a dehydration condensation reaction between diacid molecules (HOOC(CH2)nCOOH) and -NH2 functionalized Ti3C2 layers. The xDA molecules can not only tighten the adjacent layers acting as ropes during the ion insertion process but also pillar the adjacent layers when ion extraction process was used to stabilize the Ti3C2 structure by suppressing the volume change. Furthermore, the interlayer spacing of xDA-Ti3C2 can be controllably tuned from 1.03 to 1.45 nm by choosing xDA with different lengths and controlled interlayer spacings of 1.35 and 1.38 nm can be achieved for the best rate capability of insertion/extraction processes with the superior diffusion coefficient of 4.6 × 10−7/2.8 × 10−8 cm2/s in Li+/Na+ batteries, respectively.

Study on removal of organic dyes by Fe3O4/amidation modified waste polystyrene composites

Design and fabrication of structurally optimized absorbents are important for wastewater treatment such as dyes removal. Herein, modifying the environmentally harmful waste polystyrene foam as an efficient recyclable adsorbent for organic dyes is important Magnetic amidated modified polystyrene (Fe 3 O 4 /PS-SD) was prepared by Friedel–Crafts reaction, N,N”-dicyclohexylcarbodiimide (DCC) dehydration condensation, and chemical co-precipitation reaction. Fe 3 O 4 /PS-SD had highly efficient removing performance for organic dyes in large volume of water sample solutions, and the equilibrium was achieved in 0.5 h. The maximum adsorption capacity for Methylene blue (MB), Safranine T (ST), and Congo red (CR) were 620.32 mg g −1 , 679.63 mg g −1 , and 1425.77 mg g −1 , respectively, at room temperature according to the Langmuir adsorption isotherm (R 2 > 0.91). The kinetic data of the three dyes followed pseudo-second-order kinetics. After ten regeneration cycles, the removal rate remained high (> 80%). Experimental results showed that Fe 3 O 4 /PS-SD was an excellent adsorbent for water treatment with high regeneration property and thermal stability. • Modification of waste materials. • High adsorption capacity. • Separable and thermally stable. • Recyclable.

Fluorescent core-shell SiO2@vertical covalent organic frameworks nanosheets for sensing application

Fluorescent covalent organic frameworks (COFs) are attracting more and more attentions. However, it is very difficult to obtain COFs with strong fluorescence due to fluorescence quenching caused by interlaminar accumulation and intramolecular rotation. Here, the core-shell SiO2@COFTFP-TAPB (1,3,5-tri(4-aminophenyl)-benzene: TAPB, 1,3,5-triformylphloroglucinol: TFP) was prepared by assembling vertical COFTFP-TAPB through amine-aldehyde dehydration condensation reaction on -NH2-SiO2 nanospheres (NPs) for the first time. The 2D COFTFP-TAPB nanosheets with thickness of 25 nm and good crystallinity vertically stand on the surface of -NH2-SiO2 NPs based on the imine-linkage. Such core-shell structure results in larger BET surface area, effectively overcomes the interlaminar accumulation, and improves optical properties of COFTFP-TAPB. The core-shell SiO2@COFTFP-TAPB exhibits multiemission from the enol-imine form and keto-enamine form, which is sensitive to pH. After loading with glucose oxidase and urease, it could be used to detect glucose and urea successfully. The detection ranges are 0.23 μM-14 mM and 1.50 μM-90 mM, and the detection limits reaches 0.07 μM and 5.14 μM, respectively. The work provides a feasible idea to overcome the interlaminar accumulation and reaggregation of COFs during application.

Electromagnetic wave absorption of inexpensive C/ZnO composites derived from zinc-based acrylate resins

Based on the abundant and low-cost zinc-based acrylate resins, C/ZnO composites were fabricated via one-step carbonization at 700 °C in a N2 atmosphere for 2 h. Zinc-based acrylate resins, which were synthesized by free-radical polymerization of butyl acrylate (BA), acrylic acid (AA) and vinyl acetate (VAc) and dehydration condensation of Zn(OH)2, provided a common source for carbon and ZnO. These materials demonstrate enhanced electromagnetic wave absorption (EMWA) behavior with tunable microwave absorption bands at 2–18 GHz, which is related to the molar ratio (mol%) of Zn(OH)2 to acrylate monomers in zinc-based acrylate resins. Remarkably, the 0.11 mol% C/ZnO composite exhibits outstanding absorption properties: the minimum reflection loss (RLmin) at 16.7 wt% loading of −34.66 dB is observed at 3.0 mm and 10.32 GHz, and an RLmin of −24.83 dB is observed at a small thickness of 1.5 mm with an effective absorption bandwidth (EAB) of 3.61 GHz. Moreover, the EAB (RL ≤ −10 dB) from the C band to Ku band is achieved by simply adjusting the thickness of the absorbers, which are superior to the other hybrids of organic carbon and ZnO. These results provide a new strategy for the preparation of carbon-based composites containing metal oxides and their application in high-performance microwave absorption.